Device for reducing the insulating strips of commutators



B. 0. SWAIN AND J. S. TIMMONS. DEVICE FOR'REDUCING THE INSULATING STRIPS0F COMMUTATORS. APPLICATION FILED APR.2, 1919.

1 359333,. PatentedNbv. 16,1920.

2 SHEETSSHEET I.

B. 0. SWAIN AND J. S. TIMMONS.. DEVICE FOR REDUCING THE INSULATINGSIRIPS OF COMMUTATO'RS. APPLICATION FILED APR. 2, m9.

1 ,359,288, Patented Nov. 16, 1920.

2 SHEETS-SHEET 2- UNITED STATES PATENT OFFICE.

BENJAMIN o. swAIN, or PHILADELPHIA, PENNSYLVANIA, AND JOHN s. rIMMoNs'on NEW YORK, N. Y.

DEVICE non RnDUcI e THE INSULATING strains or COMMU'I'ATORS.

Specification of Letters Patent.

Patented Nov. 16, 1920.

Application filed April 2, 1919. Serial No. 287,097.

To all whom it may concern:

Be it known that we, BENJAMIN O. SWAIN and J OHN S. TIMMONS; citizens ofthe United States, and residents of Philadelphia, county ofPhiladelphia, State of Pennsylvania, and New York city, county of NewYork, State of New York, respectively, have invented certainImprovements in Devices for Reducing the Insulating Strips ofCommutators, of which the following is a specification.

Our invention relates to certain improvements in the device for reducingthe insulating strips of commutators, as set forth in the patent grantedto us on the 3rd day of November, 1914, No. 1,116,158.

One object of our invention is to arrange the guide runners so that theywill move more in the arc of a circle when adjustments are necessary.

A further object of the invention is to provide means for adjusting theguide wheels so as to regulate the depth of cut and so that they willproperly bear upon the side walls of the slots.

A still further object of the invention is to locate the switch so thatit can be 0perated by the thumb of either hand, while the tool ismanually held and to design the spindle and its bearings so that it canbe readily removed and replaced when necessar n the accompanyingdrawings:

Figure 1 is a front view, the spindle bearing being in section on theline 1-1, Fig. 3;

Fig. 2 is a rear view, partly in section, on the line 2-2, Fig. 3;

Fig. 3 is a side View;

Fig. 4 is a longitudinal sectional view on the line M, Fig. 2; I I

Figs. 5 and 6 are detached views ofthe eccentric adjusting screw;

Fig. 7 is a detached view of one of the clamping studs; and Fig. 8, is adetached plan view showing the adjusting screws for the runners. V

The invention relates to a machine for reducing the height of sheets ofmica, or other hard, non-resisting insulating materials, which areplaced between the segments of a commutator, as set forth in the abovementioned patent.

Referring to the drawings, 1 is the body of the cutting device having acentral, up-

right portion 2 in which is located the electric switch 3 having thepush buttons 4 and 5. At each side of the portion 2 and cast integralwith the body 1, in the present instance, are handles 6, which are soproportioned in regard to the switch that the thumb ofeach hand can pushdown a button without releasing the grasp upon the handles.

7 1s a longltudinal slot in the under side of the body portion 1 andlocated in this slot are the guide wheels 8, which rotate freely on theeccentric pins 9 of the screws 10 adapted to threaded openings in thebody portion and held in position, after adjustment, by nuts 11. Onturning the screws 10 the wheels 8 can be raised or lowered in the slotso as to regulate the depth of cut. The wheels are beveled, as shown,and the beveled surfaces rest against the edges of the slots. When thecutting disk becomes worn its diameter is reduced and the guide wheelsare adjusted accordingly.

The cutting disk 12 is secured to a spindle 13 by a nut 14 adapted to areduced threaded portion of the spindle and is held between disks 15 and16. The spindle has a head 17 at its outer end which bears against abushing 18 mounted in the bearing 19 seoured to the face of the body 1by screws 20, or other fastenings. The bushing has a flange 21 at theforward end adapted to a recess in the bearing and takes the thrust ofthe disk 15. The outer end of the bushing is threaded and a coupling cap22 is adapted to this threaded portion and has an internal portionthreaded for the shaft casing, the stem of the shaft extending into theopening 23 in the spindle 13, shown by dotted lines in Fig. 1.

24 is an oil cup which extends into the opening 24: in the bushing andholds the bushing against rotation. This construction allows for theready removal and replacement of the spindle and bushing, as

well as the cutting disk.

The guide runners 25 are pivotally mounted on the body 1, one at eachside, as shown in the drawings. Each pivot is in the form of a clampingstud 26, Fig. 7, which passes through the bearings 28 and the reducedportion passes through the pivot opening in the runners. The threadedportion is adapted to a threaded opening in a bearing 29 so that, onturning the clamping enlarged openings in the arms 33 of the runners 25,and nuts 36 and 37 are mounted on the screw rods 30 and 31,respectively. By turningthese nuts, the runners 25 can be turned ontheir pivots and, after adjustment, can be held by the clamp studs 26.By this construction accurate adjustment is secured.

The advantage of the guide runners lies in I the radial adjustment. Onlarge diameter commutators, the greater span of these run ners gives themaximum stablhty, while on a small diameter commutator, these runnersmore nearly approach the axis of the cominutator, thus assuringstability so that in either extreme the greatest stability is attain'ed.

We claim:

1; The combination in a device for reducing the insulating strips ofcommutators, of

a body portion; a rotating cutter mounted thereon; a guide back o1 thecutter arranged to travel in a kerf made by the cutter; and means forvertically adjusting the guide.

2. The combination in a device for reducing the height of the insulatingstrips of commutators, of a body portion having a longitudinal slottherein; two circular guides mounted to turn freely in the slot; acutter; bearings therefor mounted on the body portion; and means forindependently and verticallyr adjusting the guides.

3. The combination of a body portion; a

cutter mounted thereon, the body portion having a longitudinal slottherein in line with the cutter; two rotary guide wheels mounted in theslot; two screws mounted in threaded openings in the body portion, eachhaving an eccentric pin on which the guide wheels are mounted so that onturning the screws the guide wheels can be adjusted. a. The combinationofa body portion; a cutter mounted on the body portion; guides back 01"the cutter adapted to travel in the kerf made by the cutter; and guiderunners pivotally mounted, one on each side of the body portion.

5. The combination in adevice for reducing the height of the insulatingstrips of commutators, of a body portion; a cutter; guide runnerspivotally mounted on the body portion on each side of the cutter; and

means for retaining the guide runners in the position to which they areadjusted.

6. The combination in a device for-reducing the height of the insulatingstrips of commutators, of a body portion; a cutter; guide runnerspivotally mounted on the body portion on each side or" the cutter; meansfor retaining the guide runners in the position to which they areadjusted; and means for adjusting the guide runners.

7. The combination of a body portion; a cutter mounted on the bodyportion; two guide wheels back of the cutter and arranged to travel inthe kerf made by the cutter; two guide runners pivotally mounted on thebody portion, one on each side of the cutter; a clamping stud forming apivot and means for clamping the runners in the position to which theyare adjusted; two screw rods pivotally mounted on the body portion andextending through openings in arms projecting from the guide runners;and nuts on the rods for adjusting the run- 11ers.

8. The combination in a device for reducing the insulating strips ofcommutators, of

a body portion; a bearing mounted on the body portion; a bushing locatedin the bearing, said bushing having a flange at one end and a screwthread at the other end; a spindle mounted in the bushing; a cuttingdisk carried by the spindle, said spindle having an opening therein forthereception of a driving shaft; and a coupling cap adapted to thethreaded end of the bushing.

9. The combination in a device for reducing the insulating strips ofcommutators, of a body portion; a bearing mounted on the body portion; abushing in the bearings; a

spindle mounted in the bushing; a cutting disk carried by the spindle;said spindle having an opening therein for the reception of the drivingshaft; a coupling cap secured to the bushing; and an oil cup screwedinto the bearing and extending into an opening in the bushing,preventing the turning of the bushing in the bearing.

10. The combination in a device for reducing the insulating strips ofcommutators, of a body having an upright portion; a handle on each sideof the upright portion; a switch mounted in the upright portion. andhaving push buttons, the handles being so proportioned in respect to theupright portion that the switch can be operated without releasing thehold on the handles.

In witness whereof we aflix our signatures.

BENJAMIN O. SWAIN. JOHN SJTIMMGNS.

